Method of forming brake drums



Fr sor'w SR 53 REFERENCE.

5 Jan. 10; 1939.

F. H. LE JEUNE I IETHOD OF FORMING BRAKE DRUMS Filed Dec. 9, 1935 SEARCH ROC 2 sheets-sheet 1 11v VENTOR I FRANK mwzuus A TTORNE VS 939- F. H. LE JEUNE 2,143,445

um'acn or poaunm BRAKE mums Filed Dec. 9, 1935 2 sheets-sheet 2 IO k INVENTOR FRANK H. LQJEUNE A TTORNE VS new.

UNITED STATES PATENT OFFICE MITHOD or some isms name Frank 1!. he Jeane, Detroit, Mich, a-lgnor to Kelsey-Hayes Wheel Company," Detroit, melt, aeorporationeineiawale Application December a, ms. Serial No. 53,621- can. (01. 20-15:.

The invention relates to the manuiacture oi to 8 inclusive, I start with the blank I oi flat brake drums and reiers more particularly to the stock having a rectangular section. This blank method oi iorming brake drums ior use with is oi indeterminate length. The first step conmotor vehicle wheels. slats in cutting the blank to predetermined The invention has ior one oi its objects an inilength. aiter which it is hooped and its adjacent 5 proved method oi iorming a ribbed brake drum. ends are welded together. 'Then the dash at file The invention has ior another object to provide outside and inside and at the ends oi the blank a method of iorlning a ribbed brake drum from is trimmed, the blank I at this time being aneither iiat stock or a casting, the method being nular and endless and having a rectangular cross such that it may be readily carried out and the section with predetermined maximum transverse 1o brake drum iormed thereby will be structurally dimensions. as shown in Figures 5 and 6. The strong, blank is also oi less diameter than the brake ring These and other objects of the invention will I which is to be iormed from the blank. become apparent from the following description, The annular blank I is then heated to a suit-' taken in connection with the accompanying able temperature, which preierably ranges irom i5 drawings, in which 1000 degrees I". to 2100 degrees 1''. Aiter it is so Figure 1 is an elevation oi a portion oi a brake heated, it is rolled between the inner and outer drum made in accordance with a method emrolls 0 and il respectively. The inner roll has bodying my invention: 7 a cylindrical surface to iorm the annular blank Figure 2 is a cross section on the line 2-2 oi with an integral cylindrical brake suriace. The ,0

Figure 1 outer roll is provided with annular ribs ior en- Figure 3 is a plan view oi the original blank suing the external surface oi the annular blank. from which the brake drumismade; These ribs operate upon the annular blank to Figure 4 is a crossvsection on the line 4-4 oi i pl ce mill" ly p ed Portions thereof :5 Figure 3; in a radially inward direction to iorm the an- :5

Figure 5 is an elevation oi an annular blank nular grooves II a to d sp e the end portion made from the original blank shownin l 'igures II oi the annular blank in a radially inward di 3 and 4; rection to reduce its thickness. The rolls are Figure 6 is a cross section on the line H of also shaped to confine the material of the blank so Figure 5: during the rolling, so that the portions oi the so Figures 7 and 8 are views similar to Figures 5 meter!!! 0! h blank place radially inwardly and 6 respectively illustrating the blank aiter the are displaced circu e -Hy t rease the next operation; circumierential extent oi the annular blank and Figur 9 is an elevation of another original enlarge its diameter. It will be noted that duras blank from which the brake drum may be made in! this rolling Op r e imim trims- 85 in accordance with my method verse dimensions oi the annular blank remain Figure 10 is a cross section on the line ls-le oi substant a y t e same- In ot er words. the ra- Flgure 9. dial dimension oi the section oi the blank through As illustrated in Figures 1 and 2, the composite. its i which are i r e by t e roovi and 4o brake drum comprises the brake ring I and the the axial dimension of h section f the blank back 2. The brake ring is iormed oi suitable remain s antia y un han edmaterial providing a good wearing brake gin-1m After the rolling, the annular blank is then and the back is preferably iormed oi sheet steel. suitably Sized p e ablyby re n the same to The brake ring is provided with the series of ex- P u e h br k rin I- I ternal radially extending annular ribs 3 between Imtehd 0! starting w an ular blank 45 which are the annular grooves 4, The b ak is iormed from flat stock, I may also start with an also preierably provided at one end with the an- M -1 vii- B8 shown in Figure! 9 and 10. nular portion 5 having an external diameter less This casting is preferably a centrifugal casting than that of the ribs and adapted to iit within and the same series oi steps y e used in rethe peripheral flange 0 oi the back. The brake ashi ning this annular casting to form the brake 50 ring and back are suitably secured together as by 11118 I l are used in refuhionlns the nnular welding the portion I and the peripheral flange I blank oi Figures 5 and 6. together. From the above description, it will be readily In the manufacture oi the brake drum shown seen 'that with my method the annular blank, gginFigureslandiandasillustratedinriguress whichmaybeiormediromstripstockormaybegg extent oi the blank. This circumferential extent approximately equals that of the brake ring I, but if it is slightly less it can be brought to size by stretching. It is apparent that alter the brake ring is formed it may be readily assembled with the back and the two suitably secured together as by welding. With this method, the resulting brake drum is relatively light in weight and its brake ring is amply strong and furthermore has a substantial external area for cooling by reason of the external ribs.

What I claim as my invention is: 1. In the method of forming a brake drum.

forming an annular blank having a section with predetermined maximum transverse dimensions, grooving the blank by rolling and radially displacing material of the blank. and during the rolling maintaining substantially the same maximum transverse dimensions as those of the original blank and clrcumlerentially displacing material ol the blank by the material displaced. in

groovingtheblanktotherebyinereasethediaming substantially the same maximum cross-sec tional dimensions as those of the original blank, thereby increasing the peripheral extent 0! the blank by the material displaced in forming the grooves.

3. In the method of forming a brake drum, forming an annular blank of rectangular cross section having a predetermined maximum radial thickness and a predetermined maximum axial width, rolling the blank and during the rolling displacing portions of the material of the blank radially inwardly to'i'orm grooves with a rib between adjacent grooves, and during the rolling maintaining substantially the same maximum radial thickness and the same maximum axial width as those of the original blank and circumferentially displacing the material radially crease the diameter 01' the blank.

FRANKELEJEUNE. 

